Transfer Star-Wheel, In Particular For Flexible Containers, And Method For Cooling Said Containers

ABSTRACT

The invention relates to a system for cooling a sealed portion of a container, the apparatus having a transferring arrangement for transferring one or more containers; and a plurality of cooling arrangements with one or more gripping mechanisms for gripping the containers and one or more cooling mechanisms for cooling one or more sealed portions of the containers. Preferably, the cooling arrangements are constructed and arranged to cool the sealed portions of the containers while the containers are being transferred.

TECHNICAL FIELD AND BACKGROUND ART

The present invention relates to a transfer star-wheel, in particularfor flexible containers, and a method for cooling said containers.

As is well known, in the sector of the production and filling offlexible containers there is a particularly acute need to transfer andcool, in the shortest possible time, the previously formed containers.

Generally, flexible containers comprise a pouch, usually made ofpolyethylene (PE), and a spout, able to allow the outflow of the productmaintained within the container, for instance a drink or a fruit juiceor other beverages.

This type of flexible container is formed starting from pouches providedwith an opening, whereat a portion of the spout is inserted and securedwithin the pouch by sealing.

In particular, the sealing operation involves the edges of said openingand is performed by heating means which cause a partial melting of theedges themselves, causing them to adhere to the portion of the spoutinserted into the pouch.

A particularly acute, and as yet unsolved, problem in the sector is theneed to cool the seal area to prevent the crystallisation of thematerial whereof the pouch is made, to improve its mechanicalresistance.

Secondly, there is a need to complete said cooling operation in theshortest possible time, to avoid any negative impacts on the efficiencyof the production cycle.

DISCLOSURE OF THE INVENTION

An object of the present invention is to eliminate the aforesaiddrawbacks, making available a transfer star-wheel, in particular forflexible containers, and a method for cooling the aforesaid containers,which are able to operate, without negatively impacting on theproductivity of the line for processing the containers.

Another object of the present invention is to propose a method forcooling containers which is able to optimise the productive cycle.

An additional object of the present invention is to obtain the aboveresults within the scope of a rational, reliable and economicaltechnical solution.

Said objects are fully achieved by the transfer star-wheel, inparticular for flexible containers, and by the method for cooling theaforesaid containers, of the present invention, which are characterisedby the content of the claims set out below.

BEST MODE FOR CARRYING OUT THE INVENTION

These and other features shall become more readily apparent from thefollowing description of a preferred embodiment illustrated, purely byway of non limiting example, in the accompanying drawing tables, inwhich:

FIG. 1 shows a frontal section view of a transfer star-wheel, inparticular for flexible containers;

FIGS. 2, 3, 4 show three views of a constructive element associated tothe transfer star-wheel shown in FIG. 1, in three different operativeconfigurations;

FIG. 5 shows a lateral view of the constructive element shown in FIG. 4;

FIG. 6 shows a lateral view of a constructive detail of the transferstar-wheel shown in FIG. 1.

FIG. 7 shows a plan view of the transfer star-wheel shown in FIG. 1.

With particular reference to FIG. 1, the transfer star-wheel accordingto the invention is globally designated with the number 1 and comprisesa revolving platform 2 provided with a plurality of stations 3 forflexible containers, or pouch, each of which is provided with means forgripping the containers.

In particular, the revolving platform 2 is integrally connected to asupporting and rotating shaft 5.

In absolutely new and original fashion, the transfer star-wheel 1comprises means for cooling previously sealed portions of thecontainers.

In the preferred embodiment, the means for cooling the aforesaidportions of the pouch comprise a pair of jaws 9, 10 able to approach andtouch the aforesaid portions to be cooled.

Said cooling means further comprise a conduit 6 for delivering a coolingfluid to the jaws 9, 10, a conduit 7 for the return of said fluid and aconduit 8 for discharging the cooling fluid, after said fluid hasthermally interacted with the jaws.

In the preferred embodiment, the delivery conduit 6 and the returnconduit 7 are partially contained within the support shaft 5 of therevolving platform 2. In particular, both the delivery conduit 6 and thereturn conduit 7 comprise at least a part defined by flexible tubularbodies 6 a, 7 a, positioned externally to the support shaft 5.

In the illustrated example, the flexible tubular bodies 6 a, 7 a aredirectly connected to the jaws.

With particular reference to FIG. 1, a first jaw 9 is fixed, whilst asecond jaw 10 is movable away from the first one, in order to allow aninsertion, between the jaws, of the sealed portions of a container.

In the preferred embodiment, each jaw 9,10 has a recessed portion,substantially concave, shaped complementarily to a convexity of thecontainer present at the sealed portions. Said convexity is determinedby the presence of a spout portion 4, embedded between the sealed edgesof the container, as described in the prior art.

The star-wheel 1 comprises means for actuating the second jaw 10 to moveit away from the first jaw 9.

In the preferred and illustrated embodiment, said actuating meanscomprise a plurality of rod-like elements 11, 12, 13 kinematicallyconnected to each other to define substantially an articulatedquadrilateral. In particular, the rod-like elements 11, 12 are hinged onan appendage 30 integrally connected to the fixed jaw 9, whilst thesecond jaw 10 is connected to at least one of the aforesaid rod-likeelements 11, 12, 13. The actuating means further comprise a cursor 14slidably movable with reciprocating motion along a support guide 15,positioned on the revolving platform 2 at a pre-set distance from thesupport shaft 5.

Also present is a connecting rod 16 having a first end 16 a connected toone of said rod-like elements 11, 12, 13 (specifically to the rod-likeelement designated by the number 13) and a second end 16 b connected tothe cursor 14.

The means for actuating the second jaw 10 further comprise a secondguide 17 positioned around the support shaft 5 of the revolving platform2 and within which is engaged a roller 18 pivotally engaged to thecursor 14. The guide 17 is substantially a desmodronic guide.

In the preferred and illustrated embodiment, the means for gripping thecontainers comprise a pincer 19 located on the support guide 15 andpositioned on the revolving platform 2 at a pre-set distance from thesupport shaft 5.

In particular, the star-wheel 1 comprises means for moving each pincer19 in a direction that is substantially radial to the revolving platform2.

With particular reference to FIGS. 1 through 5, the means for movingeach pincer 19 in the radial direction comprise a sliding seat 20 for aframe 21 of the pincer and a discoidal body 22, connected to the supportshaft 5 and having a groove 23 which substantially defines a cam.

The means for moving each pincer 19 further comprise a roller 24connected to the frame 21 of the pincer and slidably housed in thegroove 23 present on the discoidal body 22.

The operation of the invention is as follows.

The containers are picked up from a forming and sealing station by meansof the pincers 19.

Subsequently, the pincers 19 move rearwards in the radial directiontowards the support shaft 5, by effect of the rotation of the platform 2and of the simultaneous sliding of the roller 24 of the frame 21 of eachpincer within the groove 23. In this way, the just sealed portions ofthe containers come in contact with the fixed jaw 9. Simultaneously, themovable jaw 10, initially far from the fixed jaw 9 to allow the pincersto grab the container, is approached to the latter by effect of thevertical and upwards motion of the cursor 14 along the support guide 15.

Said movement of the cursor 14 is caused by the rotation of the platform2 and by the simultaneous sliding of the roller 18 inside the guide 17,which is of the desmodronic type.

With particular reference to FIG. 1, the movement of the cursor 14thrusts the connecting rod 16 upwards, determining the rotation of thearticulated quadrilateral constituted by the rod-like elements 11, 12,13.

The movable jaw 10 is moved away simply by inverting the direction ofmotion of the cursor 14, by means of an appropriate geometry of thedesmodronic guide 17. After positioning the sealed portions of thecontainer between the jaws 9, 10, the cooling fluid, which circulateswithin the jaws, interacts thermally therewith, cooling said sealedportions.

The cooling fluid is sent to the jaws through the delivery conduit 6, 6a and it exits therefrom through the return conduit 7, 7 a, which sendsit to a discharge conduit 8.

The method for cooling flexible containers, of the present invention,comprises the steps of:

-   -   collecting the flexible containers at the output of a first        station for forming and sealing the containers;    -   transferring the flexible containers from said first station to        a second processing station.

In absolutely new and original fashion, the method is characterised inthat it comprises a step of forced cooling of the flexible containerssimultaneously with the step of transferring the containers.

In particular, the cooling step occurs by means of indirect heatexchange with a cooling fluid, preferably water at a temperature withina range of about 12° C. to 20° C.

The invention achieves important advantages.

First of all, a transfer star-wheel and a method according to theinvention allow to optimise the productivity of an installation.

Another advantage of the present invention is given by the fact thatcooling the sealed portions allows to prevent the crystallisation ofpolyethylene, thereby improving the mechanical characteristics of thecontainers and safeguarding their integrity. Advantageously, a transferstar-wheel in accordance with the invention solves the problem ofcooling the flexible containers in an extremely rational and reliablemanner.

1. Transfer star-wheel (1), in particular for flexible containers,comprising: at least a revolving platform (2); a plurality of stations(3) for the containers positioned on said platform (2), each of which isprovided with means for gripping the containers; a shaft (5) forsupporting the revolving platform (2), characterised in that itcomprises means for cooling previously sealed portions of thecontainers.
 2. A transfer star-wheel as claimed in claim 1,characterised in that said means for cooling previously sealed portionsof the containers comprise: at least a pair of jaws (9,10) for grippingsaid portions of the containers; at least a conduit (6,6 a) fordelivering a cooling fluid to at least one of said jaws (9,10); at leasta conduit (7,7 a) for returning the cooling fluid from said jaw (9,10);at least a conduit (8) for discharging the cooling fluid after it hasthermally interacted with at least one jaw (9,10).
 3. A transferstar-wheel as claimed in claim 2, characterised in that said pair ofjaws (9,10) comprises a first fixed jaw (9) and a second jaw (10),movable away from the first one, to allow an insertion of the sealedportions of a container between said jaws (9,10).
 4. A transferstar-wheel as claimed in claim 3, characterised in that it comprisesmeans for actuating said second jaw (10) to move it away from the firstone.
 5. A transfer star-wheel as claimed in claim 4, characterised inthat said actuating means comprise: a plurality of rod-like elements(11,12,13) kinematically connected to each other in order substantiallyto define an articulated quadrilateral, two of said rod-like elements(11,12,13) being pivotally connected to an appendage (30) integrallyconnected to said fixed jaw (9), the second jaw (10) being connected toat least one of the rod-like elements (11,12,13); at least a cursor (14)slidably movable with reciprocating motion along a support guide (15),positioned on the rotating platform (2) at a pre-set distance from thesupport shaft (5); at least a rod (16) having a first end (16 a)connected to at least one of the rod-like elements (11,12,13) pivotallyconnected to the appendage (30) and a second end (16 b) connected tosaid cursor (14); a second guide (17), serving substantially as a cam,positioned around the support shaft (5) of the revolving platform (2)and operatively active on a roller (18) pivotally engaged to said cursor(14).
 6. A transfer star-wheel as claimed in claim 2, characterised inthat said delivery conduit (6,6 a) and said return conduit (7,7 a) areat least partially contained within said support shaft (5) of therevolving platform (2).
 7. A transfer star-wheel as claimed in claim 6,characterised in that the delivery conduit (6,6 a) is at least partiallydefined by a flexible tubular body (6 a) positioned externally to thesupport shaft (5) of the revolving platform (2).
 8. A transferstar-wheel as claimed in claim 6, characterised in that the returnconduit (7,7 a) is at least partially defined by a flexible tubular body(7 a) positioned externally to the support shaft (5) of the revolvingplatform (2).
 9. A transfer star-wheel as claimed in claim 1,characterised in that the gripping means comprise at least a pincer (19)positioned on the revolving platform (2) at a pre-set distance from thesupport shaft (5).
 10. A transfer star as claimed in claim 9,characterised in that it comprises means for moving each pincer (19) ina radial direction.
 11. A transfer star as claimed in claim 10,characterised in that said means for moving each pincer (19) in a radialdirection comprise: at least a sliding seat (20) for a frame (21) of thepincer (19); a discoidal body (22) connected to the support shaft (5)and having at least a groove (23) substantially defining a cam; at leasta roller (24) connected to the frame (21) of the pincer (19) andslidably housed in said groove (23) present on the discoidal body (22).12. A transfer star as claimed in claim 2, characterised in that thedelivery conduit (6,6 a) and the return conduit (7,7 a) are directlyconnected to at least one of said jaws (9,10).
 13. A method for coolingflexible containers, comprising the steps of: collecting the flexiblecontainers at the output of a first station for forming and sealing thecontainers; transferring the flexible containers from said first stationto a second processing station, characterised in that it comprises astep of forced cooling of the flexible containers simultaneously withsaid step of transferring the containers.
 14. A method as claimed inclaim 13, characterised in that said cooling step occurs by indirectheat exchange with a cooling fluid.
 15. A method as claimed in claim 14,characterised in that said cooling fluid is water at a temperaturewithin a range of about 12° C. to 20° C.
 16. An installation for fillingflexible containers, comprising: at least a star-wheel for forming theflexible containers, by sealing portions thereof; at least a star-wheelfor filling the flexible containers; at least a transfer star-wheel fortransferring the formed containers, from the forming star-wheel to thefilling star-wheel, characterised in that said transfer star-wheelcomprises means for cooling the previously cooled portions of thecontainers.